Ash log.....how to best split

[Mark Fisher]

OK, I'm not sure whether this was a good idea, but I just got a 6 foot x15" dia ash log from my neighbor for free. I want to use to make a set of Boggs-style chairs The tree was 90% dead. The videos on youtube make the splitting look easy. So, what should I do? Should I wait a bit before splitting? I don't expect to use the wood until September. Should I at least de-bark it now? Any other advice would be appreciated!

[Jim Koepke]

Most of my splitting experience is for firewood. Green wood seems to split easier than dry wood.

I would knock off the bark. Some bugs find a layer of bark to be quite the cozy place to hang out.

jtk

[Bob Glenn]

You will need at least two iron wedges, a sledge hammer and a couple gluts. Start the split at one end in the middle of the log with the iron wedges. It will help to start the wedges in the end grain until the split starts to open. The first split will be the hardest. Hopefully, you have a nice straight grained log which will aid the process. As the split opens, work the wedges down the length of the log until the split is open enough the insert a glut. Alternate driving and moving wedges and gluts down the log until the log opens. There maybe some fibers that hang between the two halves. cut these with an axe. What ever you do, DON'T put your hand into the split for any reason.

Cutting the log in half will make this job a lot easier if you don't need full six foot pieces. Always try to make your splits so as to divide the log evenly lengthwise with equal mass on both sides of the split. Good luck.

[Mike Holbrook]

Nocking off the bark may not be advisable as the bark may help hold moisture in. Then again, as Jim says there can be bug issues. There are wood sealers or paint that are frequently used on the end of logs to keep moisture from escaping too fast. My experience has been, you want to control the moisture movement, preventing large moisture differences in different parts of the wood, which causes splitting.

On the other hand, you can split the wood into smaller more workable sizes while it is green and splits much easier. Smaller pieces of wood can adjust moisture content more evenly and tend to split less. Some chair makers split their wood while it is green and store roughed out pieces for finishing later. The dried wood is harder to work but if most of the work is done while it is green then time & effort may be saved.

A drying kiln can dry smaller roughed out pieces quickly. Most chair classes take five days to a week. They start with green wood and at the end of the class the pieces are usually stable. This is done simply by placing the wood, not being worked, in a kiln in the class. I have not made my kiln yet as I am about to move to a new home. For now I use plastic trash bags that I fill with "wet/green" drawknife and spokeshave shavings. I place the wood I am using in those bags when I am not working it. I open the bags and air the wood out every day or two and of course when I am working the wood. This helps control the drying process. A kiln is better. This may not totally control splitting but it helps a good deal.

[Mike Holbrook]

Ash can be a little difficult to split at least in the trees I work with. The trees here are not the straightest though. I think it helps to mark a notch/line across the entire end of the log. I think a wider wedge helps too. I bought a couple small axe/hatchets for starting splits in smaller logs. They can also be used to cut the threads that develop in the split. Try making the first split along a natural crack running through the center of the log, if you can find one. Larger logs may require two wedges to get the split in the end started.

A froe may help too. Lie Nielsen makes one from a Drew Langsner design. The froe can be used to mark the splitting line too. A fore just want make splits in big logs. It is used more to expand and control the "run out" from the split. Check out Curtis Buchanan's YouTube videos, there are like 40. He starts with a full size log......

[John Vernier]

I split a bunch of ash three years ago and found it pretty easy to work, as long as the grain was straight. I had some pieces with slight twist which I managed to get ok pieces out of, and some large branch sections with unbalanced "reaction wood", which were worthless. I see no reason to wait to start - the wetter the wood, the easier the splitting, and besides if it starts to dry the log may start to check wherever it pleases - by splitting it now you get to decide where the major fault lines go, as long as everything is sound to begin with.

Ash is a relatively dry wood - not a lot of excess water in the fresh-cut wood. I found it quite agreeable to work green, and it didn't shrink a great deal. I was working some green beech at the same time and the difference was remarkable- the beech was like working a saturated sponge by comparison, and the shrinking and checking much more of a problem. I spoke to Peter Follansbee when I was getting started with the ash, and he warned me to use it up quickly, as it can rot and get attacked by bugs if it sits around on the ground. However, I am lucky that I was able to store my wood under a car port roof, on a concrete slab, and it is holding up very well nearly 3 years later - which is fortunate, because I ended up with a lot of it. I split all the log sections (it was a 24" trunk at the base) into quarters or eighths, which are still sizeable pieces, but I'm finding that they still split pretty well three years later. I painted the ends of the sections with latex paint and kept the bark on. It stays under a tarp in my carport but it's able to get some air flow. So far so good.

I pretty much agree with Mike H's recommendations for splitting. I use an axe with a froe club to score a line on the end grain to define each split, and that seems to help. Once you have the logs quartered, you should chop away the pith if it is twisty, before making finer splits, as it will just make your life difficult.

[Mark Fisher]

Thanks for the great advice.....I guess I know what I'm doing tomorrow.

[Jim Ritter]

Here is a link to some serious splitting.
https://youtu.be/Y12PN8gaQ4Y

Jim

[Stew Denton]

Hi Mark,

As always, there are far more knowledgeable folks on this site than I am about this subject, but.....

In my view, logs should be split as soon as is practically possible due to the way wood shrinks. Wood, as we all know does not shrink uniformly as it dries. If it shrank uniformly it would not split, but it does.

Here is why it splits, when left as a log when drying out. We all know that boards shrink across the flat sawn direction (tangent to the tree) more than across the quarter sawn direction (perpendicular to the growth rings.) (It shrinks almost not at all lengthwise.) What this means, in practical terms, is that the circumference of the tree wants to shrink relatively more than the diameter of the tree.

Wood database has a good discussion on wood dimension shrinkage on drying, and lists that most lumber shrinks about 3 to 5% (average 4%) radially when going from wet (freshly cut) until it is dry, and about 3 to 12% (average 7.5%) tangentially (around the circumference), so lets do the math. If we start with an "average" tree 10 inches in diameter and it dries completely, the diameter would shrink 4%, which would result in a final diameter of the tree of 9.6", and yield a corresponding circumference of 30.144 inches. However if you consider the tangential shrinkage, and start with the same tree having a diameter of 10", this results in a circumference of 31.4 inches. Now, if the tangential (flatsawn) shrinkage is 7.5%, as per the wood database, this give a loss of 2.355 inches, giving a final circumference of 29.045inches.

Thus, the difference in the circumference between what the radial shrinkage wants to yield and what the tangential shrinkage wants, is 30.144 - 29.046 inches, or 1.099 inches. This amounts to a difference a bit over 1&1/16 inch. Something has to give. What gives is that the tree splits lengthwise, with a crack that is about 1" wide at the outside edge tapering to a zero at the center of the log, either that or there a lot of big checks in the resulting lumber.

Coating the end of the tree with wax or some other coating only SLOWS the rate of moisture loss, it does not stop it. What this does is buy you some time until the tree must be split before it will have a lengthwise split. Thus coating the end grain only slow the amount of time it takes for the log to split. If the log dries out before being split or cut into lumber it will still split, the only question is when. The shrinkage properties of the lumber drive this.

You still need to coat the ends of the boards after you saw them up, or the billets after you split them, because this coating will prevent drying through the end grain, and force it to dry through the sides. This will yield much more uniform drying. If you don't coat the ends, the ends dry first, shrinking the lumber on the ends, and this uneven drying will also cause splits.

Stew

[Alfred Kraemer]

OK, I'm not sure whether this was a good idea, but I just got a 6 foot x15" dia ash log from my neighbor for free. I want to use to make a set of Boggs-style chairs The tree was 90% dead. The videos on youtube make the splitting look easy. So, what should I do? Should I wait a bit before splitting? I don't expect to use the wood until September. Should I at least de-bark it now? Any other advice would be appreciated!

I just split a couple of 5 ft sections of straight ash - about the same diameter as yours.
The first split was the toughest - halving the log. It took two good steel wedges and four gluts.
Those wooden wedges were made from some of the smaller branches of the same ash tree. The gluts were about 3 to 4 inches thick and about a foot long. It took some effort widening the split from one end and on both opposite ends of the circumference. Once the split was started ok I widened them with the gluts, and if needed I used the steel wedges again - to continue the split.
The darker heartwood was tougher, and while the split was very straight, there was some 'stringy' heartwood that kept the split log sides from falling away. I separated those with an axe. Didn't have to whack at it, just a few well targeted light cuts took care of that.
The subsequent splits were easier - I did them radially for now.
All in all, not too bad - just not quite a easy as seen on tv, and it did remind me of the importance of gluts in the splitting process. They do the main work, the steel wedges are just used to get the split started.

Good luck,

Alfred

[Mark Fisher]

Well, I managed to get it split into three pieces so far. The first split took about 2 hours with two iron wedges, a plastic wedge, and a shovel (in lieu of a crow bar) The second about 15 minutes. I'm not sure it was smart to start with a log this big, but who says I'm smart!

[John Vernier]

You might be able to work faster with gluts, wooden wedges which are bigger than the iron ones and help drive the split open once it is well started by the iron wedges. I made some quick gluts from low-quality firewood splits in a few minutes, using a hatchet. I used the hardest wood I could get my hands on, apple since I had it, but any hardwood would probably do in a pinch.

[Mike Holbrook]

Maybe this will help:

Hard to tell from the picture but this was a practice red oak log with a hump on one side, a rotted area and wonky grain. But it still split fairly well/quickly by following certain steps..

*click pictures to enlarge*

Make a line.jpg Split starts.jpg Glut.jpg DblGlut.jpg

#1 -Make a line across the middle, any existing crack will help #2 -start the split, on a log this size I used two wedges, one on each side. The middle "wedge" is a maul head I used to mark the line. #3 -once the split gets going drive a glut in with a wood club to spread the crack #4 - if necessary use multiple gluts to finish the split. Further splits get even easier.

The gluts are dogwood from a dead dogwood I found in the woods. I believe the club is white oak, not sure, cut the tree in winter.

[Mark Fisher]

Thanks. The log is about 7' long so I ended up starting the split on the end similar to want you are showing except I started on the corner. I got the split going and walked it down one side of the log. Once I had it started, it really wasn't nearly as hard as I expected. Getting it started is definitely the hard part. Now I am just waiting for some reasonably cool weather to finish up!